The antihistamines that make you drowsy are first generation antihistamines like benadryl that research has suggested are very bad to take more than occasionally (linked to dementia risk, etc.)

If you need something for sleep I highly suggest you either try melatonin if you want something OTC or talk to your doctor for something that requires a prescription.

Aside from melatonin, pretty much every OTC sleeping drug you can get is an anticholinergic drug which is better to avoid.